1. This post is a tentative, partial, review of the legal status of some Muslim marriages in Ireland.
2. The civil and religious laws of some (indeed many) Muslim countries permit polygamy.
3. Under common law polygamy is not lawful in Ireland. That is to say, a marriage contracted in Ireland is monogamous or it is not a valid marriage. A person so married who partakes in a valid ceremony of marriage while the first marriage is still subsisting, will commit the crime of bigamy.
4. Irish law on polygamy is, reputedly, as set out by Lord Penzance in Hyde v Hyde and Woodmansee  LR 1 P&D 130 where marriage was defined in these terms (at 133):
I conceive that marriage, as understood in Christendom, may for this purpose be defined as the voluntary union for life of one man and one woman, to the exclusion of all others.
And at p. 138 he said..
This court does not profess to decide upon the rights of succession or legitimacy which it might be proper to accord to the issue of the polygamous unions, nor upon the rights or obligations in relation to third persons which people living under the sanction of such unions may have created for themselves. All that is intended to be here decided is that as between each other they are not entitled to the remedies, the adjudication or the relief of the matrimonial law of England.
5. In that case the husband had petitioned for the dissolution of a Mormon marriage (permitting him to take more than one wife). His claim for matrimonial relief was rejected. (Neither party had contracted a second marriage; the objection was to the fact that the marriage was potentially polygamous).
6. Of course there have been very significant changes in the law of Britain and Ireland since the judgment in Hyde v Hyde. Each jurisdiction has made provision for divorce. Thus, a modern marriage in either jurisdiction does not conform to Lord Penzance’s definition of a marriage. It is very likely, on a proper interpretation of Hyde v Hyde that it cannot, by that token alone, be declaratory of the law in Ireland.
7. The UK, however, recognising the serious difficulties that the law as framed by Hyde v Hyde caused to some Muslims, particularly women, took steps to reduce those difficulties and expressly varied its law with Section 47 (1) of the Matrimonial Causes Act 1973 (amending the Matrimonial Proceedings (Polygamous Marriages) Act 1972), subsequently, again, changing the law with Section 5 of the Private International Law (Miscellaneous Provision) Act 1995. The Section reads:
Validity in English law of potentially polygamous marriages.
5. -(1)A marriage entered into outside England and Wales between parties neither of whom is already married is not void under the law of England and Wales on the ground that it is entered into under a law which permits polygamy and that either party is domiciled in England and Wales.
(2) This section does not affect the determination of the validity of marriage by reference to the law of another country to the extent that it falls to be so determined in accordance with the rules of private international law.
8. In Ireland, under Irish conflict of laws, the law of the place of celebration prescribes the nature and incidents of a marriage. (Brook v Brook 9 H.L.C. 193) However, the law of domicile determines the capacity to marry. If under the law of domicile polygamy is not permitted, the polygamous marriage, valid under the law of the place of celebration will not be valid under the law of domicile.
9. In the case of a marriage where the law of domicile and the law of the place of celebration are the same and polygamy is permitted in that jurisdiction, the marriage will be polygamous and valid in Irish law. If the parties then change their domicile by choice and gain a domicile where monogamy only is permitted, the marriage will, in the absence of any further marriage on the part of either person, be deemed to be monogamous.
Nevertheless, as seen in Bibi v. Chief Adjudication Officer  EWCA Civ 1957 (25th June, 1997) difficulties remained. A widow of a deceased Bangladeshi man was denied Widowed Mother’s Allowance under section 25 of the Social Security Act 1975. She was the deceased’s first wife, having married him in Bangladesh in 1966. Her husband had been born in Bangladesh and registered as a British citizen on 20 September 1961 after working in the United Kingdom. The deceased married again, in 1969, in Bangladesh, lawfully so, in accordance with the law of that place. The applicant and the deceased travelled together to Britain and had a child or children there. The husband died in 1988. The court, applying Regulation 2 (1) of the Social Security and Family Allowances (Polygamous Marriage) Regulations 1975 upheld the refusal of the allowance to the widow. The law of his domicile was deemed to be Pakistan rather than Britain. (If Britain had been his deemed domicile the marriage would have been presumed to be monogamous regardless of the law of the place of celebration, i.e. Pakistan). See (Hussain v Hussain  Fam. 26)
10. In Imam Din v National Assistance Board  2 QB 213. this view of matters was shown to be a one way street. The appellant was ordered to pay maintenance to his spouse and children. His spouse was his second wife, they having married in a polygamous marriage valid according to Muslim law. The first spouse was still living. On marrying the second time he traveled with his new spouse and their children to the UK where he deserted them, leaving them destitute. Under Section 42 of the National Assistance Act 1948 he was required to maintain his wife and his children. The fact that the marriage was polygamous did not prevent the court construing the Act that the ‘wife’ was to include the wife of the polygamous marriage.
11. Despite the changes in the UK there are still difficulties for Muslims seeking matrimonial and certainly Social Welfare benefits from the UK State.
13. Given that Ireland has not made any effort to adapt to the social needs of Muslims, some of them, particularly women, will find their position unenviable and considerably more difficult relative even to the UK.